Two decades before astronauts walked on the Moon, American movie-goers got a good preview of what the trip might look like. “Destination Moon” was the first big space movie. And it was the first to accurately explain the science and engineering of a trip to the Moon.

Co-written by science-fiction author Robert Heinlein, the movie premiered 75 years ago today. In the story, millionaire businessmen decide to finance a lunar voyage. They build a nuclear-powered rocket in the desert, then send it on its way. Problems ensue, but the crew lands on the Moon and makes it back home safely.

The backers are convinced in part by a short cartoon that accurately explained how rockets work. In fact, the cartoon was so good that NASA later used a revised version to explain rockets to the public.

Destination Moon also showed the effects of acceleration and zero-gravity. During a spacewalk, one of the crew maneuvered using a tank of oxygen; the first real American spacewalker used a similar technique. And on the Moon, the crew loped along just like the Apollo astronauts.

The film didn’t get everything right. The landscape – painted by space artist Chesley Bonestell – was too sharp and craggy. And the art director added cracks to the surface like those in a dry riverbed to add a feeling of depth.

Still, Destination Moon remains one of the most accurate movies about spaceflight – a fantastic trip to the Moon long before the real thing.

Script by Damond Benningfield